Power press



, May 8, 1945. W, s, WlLKlNs I 2,375,398

POWER PRESS Filed Feb. 25, 1943 3 sneers-sn'eefl' POWER PRESS l Filed Feb. `25, 1943 s sheets-sheet 2 I I l I a, I l a T a a ad z @Li @i ////.f//////////////////////////////// a E A C l a al E R l /l/ I III/11111117' WALTER Samuel. .VVnLK/NSY .l I Ibvelbw May 8 1945. w. s. wlLKlNs 2,375,398

4 POWERv PRESS Filed Feb. .23, 1945 s sheets-sheet :s

if II-IIIIIIIIIIH Ulllllllllii 41* v3 ha INVENro/z Wzferawizins;

Arm/mgm Patented May 8`, 1945 y 2,375,398f POWER PRESS:

e Walter Samuel-'Wilkinsg Wednesbury; IiinglandI AppIication,February` 23, 1943, ScralNo..4316,864i K In.Great Britain May-.15,1942 l .e e

The invention relatesV to power presses,` vand more especially to power-:presses of, the type in which anupper; moving headis; impelled ,downwardly. by power. means` situated beneath atflxed lower bed orl bolster,` and` has florits` object to l provldelnovel ory improved means for adjusting the lengthof the stroke of the head.v l

It has been proposed lto alter the stroke-l of an ofhthekmachine supporting bearings bb. (seeFiguref,31)',fora drivingshaft B-` integral, yv vithan eccentric-driven. power pressnby altering the eccentricityfof the eccentric or eccentrics,`but; such method isdiflicult of. adjustment and limited in itsgrange.

According to this invention the moving, head ofthe press isactuated; by Aan eccentric or crank through the medium of; a lever'or levers, the pivot ofy each lever -being at anintermediate pointthereof andl formedl as` asliding part. whiche` is adjustable-along the lever to;a1ter the leverage thereof. Theeccentric or crankiis carried andldriven by a suitable driving shaft and-.actuates the moving head; through. an` eccentric` rodi4 or. connectingrod whichispivotedto one end of the: lever or one endof; each, of two f levers,j the` other {end of each of whichis drivingly connected; tothemoving head.

The Vconnection to the movinghead maycomg.- prise-arod orfrods fixed; in` relation'to the head and eachcarrying apivotedguideto receive the outer. end of. the lever; orthe connectingmeans may comprise a link for each;lever pivoted, to the-end' of the 'lever and'to the head.

v ;'Ihe. eccentric or crank ispreferably situated under thebed-:or-table andthe-eccentric, rod or pivotally` connected to thev inner endsof twolongitudinally disposed levers., y

TlWQf convenient.v embodiments 1 of the. yinvention are;v described byl way of example,` and with referencefto the acccmpanyingdrawings; of which- Figure 1, is a; vertical section ltaken on line ||of Fig; 5a; 1

,Eiga 2;.isal` section on linev2-2 of Fig. 5a; .l Fig.y 3 isa transverse section, on.V line; 3-3of Eig;` 5w, the-'eccentric and shaft elevation;v

Fig..4 isasectiOn on line 4".-4of Fig. 64illustratinga modiedformofthe invention;

is a fragmentary sectional plan view,`on line 5,-5 of Fig` 4.;

Fgga isk a plan view` Figs; 1 3.; l

- Fig; Slis asectional plan viewiofy the press; the

secftion,l beingl taken just under the head; a5 in Eafi; l Fig. 7 isa; sections-onv aplane through the cen,-

being shown in `of the press-shown in eccentric C, around which passes the strap.M d. of an. eccentric rod D; which at itsupper` end engagesqwith an transversely disposed pin df', en the endsf of vWhich are two slides d'z (see Figure 3)., guidedlbetween verticalguides a, sa.: E, E, are two longitudinallyy disposed.v levers, theI one hav.- ing,`at.its;inner enda single luge and the other apair ofi lugs ef, e-, all three lugsengaging with thepind. Each lever E is` of rectangular sec` tion butyis forked at its outer end toprovide two prongs e2,s e2 (seevespecially Figurer 2). l Each lever-E,passesuthrough ar guide slot of` a, partf cylindrical block F adapted for partial` turning movement-*about a4 horizontal pivot axis a housingy G. Thislatter is adapted for longitudinal sliding movement between guides a', a', in.-

' tegral Withtherame-A. EachhousingG with Y connecting; rod; extending upwardly. and. being f tst', andvU showninv elevation; and',y .f

surface of the head .M by two screws.

its; block F can be moved along the respective lever` E; by longitudinal screws H threading through eachblock G. The screws have rigidlyv mounted, on their, outer ends, worm-wheels h, h, engaged by. worms h', h; on transverse shafts h2 which arecoupledto a common operating worm shafty hby worm and wheel; gear. -By rotating theoperating shaft h3 the `two shafts hzare ro- ,tated and' these in turn rotate'the shafts H which move the blocks F; In this mannerthe 'fulcrums ofthe levers can be-moved simultaneously to increase or ydecrease the leverage by thefsame amount. y l' n K is the bed or'table of`- the'pres's adapted'y to carry the bottom tool or tools (not shown) and M` isthefmovable head adaptedf to carry. the upper tool` or tools` (also not shown);` Passing up :through both thetable K and head M are four ends (see Fig. 2). Thek headM isflifted through"` the medium of the nuts n and these; latter have .eachl an annular groove into which isflttedan-inturned` ledge of a washer dividedv into two parts. Each` part` ofV thev washer isk secured to the top This is wellr known practice in power presses. A(See American publicationMachinery Encyclopedia, vol. 5, page V162, year 1917,*publishers, lIndustrial Press, New

York.)l Each of the rods N has intermediate' its height an enlarged portion n' cutaway at each side to form part-cylindrical cavities n? in Whicliarelocated part'.-cylindrical-.blocks n3..` The inner faces-fofgtheseg blocks, are formed flat and are adaptedl to:` engage.: against lthe top f and;l bot.-`

2 s y l tom surfaces of the bifurcated ends e2. ofth levers E. Between vthe cavities n2 of each rod N there is left a central portion or web n4 at either .side of wnioh the bifurcations e2 pass. `The bifur'oated ends therefore act to impor the rods downwardly and they can slide longitudinally across-the rods to allow for the 'fact 4that theA y `'outer ends ofthelevers move ina curved path. Y

The part-cylindrical shapeof` blocks n2. allows for the' pivoting of thelevers E in relation to the rods N.

When the housings'G are moved-inwardlyftofwards each other, the up and down movement j ofthe outer ends of the levers E is increased and the stroke of the press lengthened. Outward movement of the fulcrum blocks hasy the opposite effect, namely that of shortening theV stroke of thepress.

At its lower end each rod N passes down into a bore in a socket P integral with the frame" A, such bore acting .as a guide and dash pot for the lower end of the rod. The socket may, however, be utilised also as the rchamber of .a pump the v lower endof --the rod N forming the plunger.

The lower ends of frame portions a2 may be kutilised as oil sumps from which oill mayr be pumped to the various vparts of the press. The eccentricstrap d may dip into the oil.

Referring to Figures 4 and' 5, the arrangement of the sliding fulcrum and the guiding of the pivot joint between the inner ends ofthe levers is similar to that which is described with refer.-Vv

ence lto the previous gures; but, 'in Figure 4, there vis rshown a connecting rod R engaging at its lowerl end with a crank pin S, and with the y levers E,y E, by a pin D'. This latter is guided as before between vertical guides@ a. l

Eachlever E is pivoted at its outer end to a vertical rod T ythreaded at its upper end to receive a spherical nut t provided with a set of peripheral teeth t with which engage teeth u of a short vertical shaft U, which is turned in the usual way to adjust the height of the' moving` head. 31:2 is a bottom bearing piece sited into the l bottom of a vertical bore m formed infroin the t3 is a gland screwed into y top of the head M. l the top of the bore m. The gland tand bearing f Vpiece t2 have their inner ends formed part spherical to fit against the spherical nut t. The bearing piecevt2, glandt3 and the metal in the head M below theA borem are boredto allow of a cerltain amount of lateral movementof the rod T as the vrespective lever E rocks.

The head Mis guided by the internal,surfaces of pillars a3- `which are of angle section and are strengthened by triangular-section corner-pieces a4'which act as additional guides. Thecorners of the head M are cutaway to engage against ytheinner faces of the corner pieces a4.v The uplper ends of the pillars a3 -areconnected together by plates a5.

for moving said fittings simultaneously along said levers to alter the stroke of the movable head.

2. A power press comprising a movablewhead,

o a fixed table towards which said movable head is impelled, a driving shaft, crank type means driven. I byv said shaft situated on the side of said table 1 remote from said movable head, a pair of levers;

extending in opposite directions and pivotally'v p connected together, each at one end, and kto saidv crankv type means, guide means for said pivotal connection, a pair of yrods adapted to be moved 'I bythe other ends of said levers and connected to Vsaid movable head to impelit towards said table, a pair of fittings forming fulcrums for said levers, and, means for moving said fittings simultaneously along said levers to altery the stroke ofthe movable head.

3.y A power press comprising a movable head, a fixed table towardsl which said movablehead is impelled, a driving shaft, cranktype means driven bysa'id shaft, a pair of levers extending in opposite directions `and. pivotally connected to gether, each at one end, and to saidcrank type r means, guide means for said pivotal connection,

Having fully describedv my inventionI what f claim yand desire to A'secure `by Letters Patent is: 1. A power press comprising'amovable head,a

fixed table towards which said movable head is impelled, a driving shaft, crank type means VdrivieriY by said shaft, apair of levers extending in opposite directions and `pivotally connectedtogether, each at one end, and -to said crank type means, guide means for said pivotal connection, a. pair of rods adapted to ybe moved by the other ends of saidlevers and connectedto said movable head to impel it towards said table, apair of ttings forming fulcrums for said levers, and means a pair of rods pivoted to the outer ends of said levers and connected to said movable head to impel it towards said table, a pair of iittings form;`

ingfulcrums for said levers, and means for mov,- ing said `fittings along said levers to alter the stroke of the movable head. Y n 4. A power press comprising a movable head,

' la xed table vtowards which said movable headis impelled, a driving shaft, crank type means driven by said shaft, a pair of levers extendingin opposite directions and pivotally connected togeth`er,each atone end, and to said crank type means, guide means for said pivotal connection, afpairof rods,v rotatable guideways carried by vsaid rods and through which the outer ends of v said levers are adapted to slide and said` rods connected to said movable head to impel` it-towards said table, a pair of fittings forming fulcrums for said levers, and means l.for moving said ttings yalong said levers'to alterthe strokeof the movable head. v f

5. A powerpress comprising a movablehead, a fixed table towards which said movable head is impelled, a driving shaft, crank type means driven by said shaft, a pair of levers extending 'in opposite directions and pivotally connected pair of fittings forming fulcrums for said' levers,V

and means for moving said fittings along'said levers to' alterthe stroke of the movable'hea'd'.

6. A power! press comprising a movable head, a fixed. table towardsl which said movable head is impelled, a driving shaft, fcrank type means driven `bysaid shaft, a pair of levers extending in opposite directions and pivotally connected together, eachv at one end, and to said crank type means, guidemeans for saidy pivotal' connection, a pair of rods adapted to be moved by the other ends `ofsaid levers and connected to said movable rhead to yimpel it towardsv said table, `'a pair of fittings forming fulcrums for said levers, I`and man's' l l for moving said vttingsalongsaid-levers to alterA the stroke ofthe movable head', Y l vWALTER. SAMU EL :WILKIN- S. 

